1. Field of the Invention
The invention concerns an unscrewing safeguard for a gradient coil connection.
2. Description of the Prior Art
Magnetic resonance apparatuses, in particular for the examination of patients by magnetic resonance tomography (MR, MRT), are known from DE10314215B4, for example.
Modern magnetic resonance systems operate with coils that emit radio-frequency pulses to excite nuclear spins to magnetic resonance and/or to acquire the induced magnetic resonance signals. A magnetic resonance system typically has a permanent magnet or (more often) a superconducting coil to generate a basic magnetic field (B0) that is optimally homogeneous in an examination region. A large coil known as a whole-body coil (also called a body coil or BC) is normally permanently installed in the MR apparatus. Multiple local coils (also called surface coils or LCs) may also be provided. To obtain information from which images of a patient can be generated, selected regions of the subject or patient to be examined are read out with gradient coils for each of three axes (for example X, Y approximately radial to the patient, Z in the longitudinal direction of the patient). The spatial coding in magnetic resonance tomography is typically achieved using a gradient coil system with three independently controllable, magnetically orthogonal gradient field coils. The orientation of the coding plane (“gradient field”) can be freely selected by superimposing the three freely scalable fields (in three directions X, Y, Z).
Conventionally, a coaxial gradient current connector is pulled through and secured to a gradient coil bushing by a cap nut with fine threading.